Passive damper bearing and gravity-gradient rod development
Eddy-current damper and gravity-gradient rod development
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Eddy-current damper and gravity-gradient rod development
Application of viscoelastic materials to gravity- gradient damper and boom technology
Flight performance of structural dampers on solar panels and waveguide antenna of Mariner IV space probe
Variable viscosity, variable stiffness dampers using polymeric materials near glass transition temperatures for shock and vibration attenuation in space environment
Attitude errors of inertially coupled gravity gradient satellite with solar radiation pressure as dominant disturbance, noting slot problems in stabilized package accommodating damper motion
Periodic symmetric two-impacts-per-cycle motion of impact damper solved, determining asymptotically stable regions
External damper effectiveness in attenuating vibration of launch vehicle near launch umbilical tower
Electric analog and mechanical model used to investigate single particle impact dampers
Individual section dampers relation to modal damping of series mass spring in lumped parameter systems
Attitude errors of inertially coupled gravity gradient satellite with solar radiation pressure as dominant disturbance, noting slot problems in stabilized package accommodating damper motion
A general methodology for damper placement in spaceborne interferometers is introduced.
This report analyzes field data to understand the impact of faults in variable air volume (VAV) terminal units on building indoor conditions and heating, ventilation, and air-conditioning (HVAC) system operations. The Oak Ridge National Laboratory (ORNL) team conducted field tests at the commercial building test facility known as ORNL’s Flexible Research Platform (FRP) building. Two specific faults-damper malfunctions and airflow sensor inaccuracies- were implemented, as these are common faults in VAV terminal units and can significantly impact HVAC system performance by increasing energy consumption, causing occupant discomfort, and raising operational costs.
SRF technology enable particle accelerators operate with greater average beam currents and higher duty cycles. In these regimes parasitic excitation of the cavity HOM spectrum become the limiting factor due to extra RF losses and instabilities appearing in the beam. We discuss the limitations of HOMs for large accelerator projects as the Fermilab MI upgrade and the proposed future circular and linear colliders EIC and ILC. A new compact HOM damper concept is suggested providing required HOM suppression. The idea is based on an oversized coaxial line with radial sections, which is directly connected to the axial region of the SRF cavity. Such radially sectioned coaxial works as a filter for the operating mode, while being transparent for the HOMs. Implementations of this design for the accelerator and crab cavities developed for the MI and EIC machines, respectively, are discussed.
The viscous pendulum damper consists of a cylinder containing round trays on which round lead slugs rest. When assembled, the container is filled with a viscous liquid and attached, with axis vertical, to the structure. The device permits varying the damping of structural vibrations.
Viscous-film damper eliminates response lag of resonance generated noise when inserted into the thrust measuring system. This technique can be applied to automated devices when pulsed force or low order impact is involved, and where signal noise is produced by stopping or reversal of mechanical travel or by water hammer.
Point vibration dampers whose basic energy absorption mechanism is elastoplastic hysteresis, supplemented by rubber damping elements
Bounds for decay times of pendulum damper vibrating in plane containing spin axis of space vehicle